Purification Methods
Recrystallise the acid chloride from *C6H6. If it is not very pure (presence of OH or NH bands in the IR), dissolve it in pyridine, shake it with phosgene in toluene, evaporate and recrystallise the residue. Carry out this experiment in a good fume cupboard as COCl2 is very TOXIC, and store the product in the dark. It is moisture sensitive. The amide has m 246.5-247o, and the dimethylaminoethylamide hydrochloride has m 197-198o. [Weston et al. J Am Chem Soc 75 4006 1953, Beilstein 20 III/IV 3841.]
